Circuit breakers are used in a wide variety of electronic systems in which components must be protected from large currents such as those that accompany circuit malfunctions or external power surges. A circuit breaker is connected between the source of power and the components to be protected, and contains a component that trips when excessive current flows through it, opening the circuit through the circuit breaker and disconnecting the source of power from the components to be protected. Electronic systems frequently include on and off switches connected in series with the circuit breaker for turning on or off the electronic system. Frequently, separate switches and circuit breakers are used in electronic systems. Since two units are used, a relatively large amount of space is required to accommodate both units.
A combined switch and circuit breaker unit is disclosed in U.S. Pat. No. 4,528,538 to Andersen. This is a single unit and is adapted so that after interruption of the current flow by the circuit breaker, opening the switch circuit resets the circuit breaker. In Andersen, however, the switch and circuit breaker are electrically separate units and are not unitary. The Andersen device is not very compact since the switch and circuit breaker are electrically separate units. The Andersen device is also relatively expensive to manufacture since it is relatively complex, and comprises numerous parts.